Joint member for concrete slabs

ABSTRACT

A joint member for concrete slabs embodying a vertical stake carrying an ear extending upwardly alongside and in spaced relation to the stake for receiving therebetween a portion of a screed sheet. A barb carried by the ear extends toward the stake and cuts into a side of the screed sheet inserted therebetween.

United States Patent [72] Inventor Ernest ll. Self Birmingham, Ala.

[21] Appl. No. 751,552

[22] Filed Aug. 9, 1968 [45] Patented Feb. 9, 1971 [73] Assignee Vulcan Metal Products, Inc.

a corporation of Alabama [54] JOINT MEMBER FOR CONCRETE SLABS [56] References Cited UNITED STATES PATENTS 1,945.784 2/1934 Myer 52/155X 3,429,241 2/ l 969 Burton 94/17 Primary Examiner.l. Spencer Overholser Assistant Examiner-DeWalden W. Jones Att0rneyJennings, Carter & Thompson 3 Claims, 4 Drawing Figs.

[52] [1.8. CI 249/9, ABSTRACT: A-joint member for concrete slabs embodying a 249/3, 25/ l 18, 52/155, 94/17 vertical stake carrying an ear extending upwardly alongside [51] Int. Cl EOlc 11/02 and in Spaced relation to the stake for receiving therebetween [50] Field of Search 249/9, 5, 3, a po tion o a screed sheet- A barb carried by the ear extends 2,219, 101, 98;25/l3lCM, 118W, 118M; 52/155; toward the stake and cuts into a side of the screed sheet in- JOINT MEMBER FOR CONCRETE SLABS BACKGROUND OF THE INVENTION This invention relates to a joint member for concrete slabs and more particularly to concrete slab key-joining forming members for use in the construction of concrete slabs for roadways, floors, runways and the like.

An object of my invention is to provide a joint member wherein the key-joint forming member in the form of a screed sheet is positively secured to a supporting stake.

A more specific object of my invention is to provide a joint member for concrete slabs of the character designated in which the supporting stake carries barb supporting members which hold the barbs in position to cut into a side of the screed sheets upon insertion thereof between the stake and its associated barbs.

A still further object of my invention is to provide a joint member for concrete slabs ,of the character designated which shall be extremely simple of construction, economical of manufacture and one which may be assembled in a minimum of time.

Apparatus embodying features of my invention is illustrated in the accompanying drawing, forming a part of this application, in which:

FIG. 1 is a side elevational view, partly broken away, showing the vertical stake secured to an elongated screed member which is employed as a key-joint forming member between adjacent slabs of pured concrete to form a tongue and groove interlocking joint therebetween;

FIG. 2 is a sectional view taken generally along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged, fragmental view showing the upper portion of the stake with the screed member being omitted for the sake of clarity; and,

FIG. 4 is a top plan view of the stake.

Referring now to the drawing for a better understanding of my invention, I show a key-joint forming member in the form of a sheet metal screed member which may be formed of any suitable material. The elongated screed member 10 comprises upper and lower, vertically extending coplanar portions 11 and 12, respectively, which are connected to each other by an intermediate, laterally disposed key deformation portion 13. The upper edge of the upper planar portion 11v is folded over on itself as at 14 to provide a downwardly extending flange 16 which lies adjacent the upper portion 11, as shown in FIG. 2, to define a narrow, longitudinal edge which extends at grade level. By forming the flange 16 adjacent the upper portion 11, no void isleft therebetween.

Longitudinally spaced openings 17 are provided through the sheet member 10 adjacent the juncture of the upper planar portion II and the key defomiation portion 13 for receiving earlike members 18 carried by a vertically extending stake 19. Preferably, the earlike members 18 are punched out of the metal forming the stake 19, as shown in FIG. 1, by short lateral slits 21 which intersect with longitudinally extending slits 22 to provide an earlike member 18 at each side of the stake 19 adjacent the upper portion thereof. As shown in FIGS. 2 and 3, each earlike member 18 extends laterally as at 23 and then upwardly as at 24 in spaced relation to the adjacent side of spike 19 whereby it is in position to pass upwardly through an adjacent opening 17 and extend alongside the opposite side of the upper planar portion 1 1 from the side thereof abutting the stake l9.

Sharp barb members 26 are carried .by the inner surface of each upstanding earlike member 18, as shown. Each barb 26 extends inwardly toward the adjacent side of the stake 19 a distance to cut into the adjacent side of the sheet member 10 upon movement of the upper portion 11 thereof downwardly between the ears l8 and the stake 19'. As the barbs 26 cut into the adjacent surface of the upper portion 11 of the sheet member, the sheet member is secured firmly to the stake 19 due to the wedging action of the barbs 26 into the cuts fonned in the side of the upper portion 1 l.

To further attach thestake 19 to the sheet member 10, vertically spaced openings 27 are provided in the stake 19in position to be in alignment with the lower portion 12 of the sheet member 10 for receiving suitable securing elements whereby the lower portion 12 is secured to the stake; The securing elements may be in the form of wire members, nails or the like commonly used in the attachment of stakes to concrete form members.

From the foregoing description, the construction and use of my improved joint member for concrete slabs will be readily understood, The stakes 19 are driven into the prepared subgrade in a manner well understood in the art to which my invention relates with the upper ends of the stakes spaced uniformly below grade level. The stakes 19 are positioned longitudinally relative to each other so that they are in alignment with the openings 17 provided in the sheet members 10. The sheet members 10 are then positioned on the stakes 19 whereby the cars 18 pass upwardly through the openings 17 with the upper planar portion 11 between the ears 18 and the adjacent side of the spike 19, as shown in FIG. 2. As the upper portion 11 is forced downwardly between the barbs 26 and the upper portion of the stake 19, the barbs cut into the upper portion 11 to firmly secure the upper portion 11 between the upstanding ears 18 and the stake 19. The member 10 is moved downwardly relative to the stake until the bent over portion 14 is at grade level.

From the foregoing, it will be seen that I have devised an improved joint member for concrete slabs which is particularly adapted for forming a key contraction joint between adjacent concrete slabs. By firmly anchoring the elongated sheet member 10 between the ears 18 and the adjacent side of the stake, due to the cutting action of the barbs 26 into the side of the upper portion 11, the elongated sheet member 10 is accurately positioned on the stakes and secured thereto with a minimum of other securing means. The openings 27 are provided in the stake 19 for receiving an additional securing element merely to restrain any pivotal movement of the upper portion of the stake relative to the opening 17. That is, the openings 27 assure that the barbs 26 remain in firm contact with the cut portions formed in the adjacent surface of the upper portion 11. Also, by providing the anchoring of the barbs 26 into the cut portions of the upper portion 11, the

I overall structureis sturdy and positions the stakes accurately in at right angles to the upper edge of the forming member 10.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof,

1. In an article of manufacture used in supporting an elongated vertically extending screed sheet for forming a contraction joint between adjacent concrete slabs:

a. a vertically extending stake;

b. at least one earlike member carried by an upper portion of said stake and extending upwardly alongside and in spaced relation to the adjacent side of said stake for receiving a portion of said screed sheet therebetween; and a barb member carried by said earlike member extending horizontally inward toward said adjacent side of said stake a distance to cut into the side of said screed sheet upon insertion of said portion of the screed sheet between said barb member and said adjacent side of the stake to secure said adjacent portion of the screed sheet therebetween.

2. An article of manufacture as defined in claim 1 in which each earlike member is punched out of the material forming the stake with each earlike member extending laterally from and then upwardly alongside said upper portion of the stake.

3. In a concrete form for forming a key contraction joint between adjacent concrete slabs wherein a plurality of stakes are set with their upper ends spaced uniformly below grade level at spaced apart intervals:

a. an elongated sheet member having spaced apart upper wardly from and in spaced relation to each stake in psiand lower vertically extending coplanar portions abutting tion to pass upwardly through an adjacent one of said lonthe Stakes and Connected to each other y an inter gitudinally spaced openings alongside the opposite side of mediate, laterally disposed key deformation P said upper planar portion from the side thereof abutting b. the upper edge of the upper planar portion being folded 5 1 the Stakes; and

over on itself and extending downwardly against said upper planar portion to define a narrow, longitudinal edge extending at grade level;

0. there being longitudinally spaced openings through said sheet member adjacent the juncture of said upper planar l0 portion and said key deformation portion;

d. at least one earlike member extending laterally and upe. a barb member carried by each earlike member extending toward said opposite side of said upper planar portion a distance to cut into said opposite side and secure the adjacent portions of said upper planar portion between said barb member and its stake. 

1. In an article of manufacture used in supporting an elongated vertically extending screed sheet for forming a contraction joint between adjacent concrete slabs: a. a vertically extending stake; b. at least one earlike member carried by an upper portion of said stake and extending upwardly alongside and in spaced relation to the adjacent side of said stake for receiving a portion of said screed sheet therebetween; and c. a barb member carried By said earlike member extending horizontally inward toward said adjacent side of said stake a distance to cut into the side of said screed sheet upon insertion of said portion of the screed sheet between said barb member and said adjacent side of the stake to secure said adjacent portion of the screed sheet therebetween.
 2. An article of manufacture as defined in claim 1 in which each earlike member is punched out of the material forming the stake with each earlike member extending laterally from and then upwardly alongside said upper portion of the stake.
 3. In a concrete form for forming a key contraction joint between adjacent concrete slabs wherein a plurality of stakes are set with their upper ends spaced uniformly below grade level at spaced apart intervals: a. an elongated sheet member having spaced apart upper and lower vertically extending coplanar portions abutting the stakes and connected to each other by an intermediate, laterally disposed key deformation portion; b. the upper edge of the upper planar portion being folded over on itself and extending downwardly against said upper planar portion to define a narrow, longitudinal edge extending at grade level; c. there being longitudinally spaced openings through said sheet member adjacent the juncture of said upper planar portion and said key deformation portion; d. at least one earlike member extending laterally and upwardly from and in spaced relation to each stake in position to pass upwardly through an adjacent one of said longitudinally spaced openings alongside the opposite side of said upper planar portion from the side thereof abutting the stakes; and e. a barb member carried by each earlike member extending toward said opposite side of said upper planar portion a distance to cut into said opposite side and secure the adjacent portions of said upper planar portion between said barb member and its stake. 